Bracket jack



July 19, 1938. .R. ROBISON ET A1.

BRACKET JACK Filed May 22, 1957.

INVENTORS Rama-'4 Ros/:0

GEOQGEMMQu-L ATTORNEY.

Patented July 19, 1938 PATENT OFFICE BRACKET JACK Russel Robison, San Francisco, and George H.

Mosel, Burlingame, Calif.

' Application May 22, 1937, Serial No. 144,212

6 Claims. (01. 254-98) This invention relates to screw jacks generally, but particularly to a. screw jack for special 4 use in servicing automobiles. The principal obf ject of the inventionis to provide a portable quick operating screw'jackwith a frame adapted to'cooperate with the frameof an automobile hoist for lifting any desired part of an automobile already elevated. on the hoist.

A particular object of the invention is a screw hoist of this type provided with a split nut for quick adjustment and/or removal of the screw.

A further feature is to provide a special split nut in a screw jack which will automatically lock itself against opening when pressure is 15'" applied.

A further object is toprovide a construction which may be packed flat on its frame.

A still furtherfeature is ,to provide a supporting bracketwhich may be extended to straddle any automobile hoist frame or garage pit.

Other features and advantages of the construction will appear in the following description and accompanying drawing.

In the drawing:

Figure 1 is a side elevation of our improved bracket jack, indicated as supported on the frame of a cylinder type automobile hoist.

Figure 2 is a plan view of our jack.

Figure 3 is a cross section of Figure 1, as seen from the line 3-p-3 thereof. a

Figure 4 is an enlarged cross, section of the split nut and its carriage as seen from the line 4-4 of Figure 2.

Figure 5 is a detached vertical section of one "*iaw of the split nut.

Figure 6 is an elevation of a modified form of our bracket jack applied directly to the cylinderof a cylinder type automobile hoist.

Before describing the invention in detail, it

will simplify the understanding of the same to state that our special-bracket jack is principally intended for use in connection with service station hoists of the cylinder or other type which bodily lift the car up, for after it is thus lifted up it is frequently desirableto forcethe chassis of the car still further up in reference to the springs for greasing and/or adjusting the same, and it is here .where our bracket jack has particular value. l

Our jack is provided witha specialsupporting bracket whichis adapted to engage the hoist;

structure upon which the automobile has already been raised, and along which bracket" the splitnut carriage of "our 1 jack vmay be 'adjusted to bring the jack screw directly under any part, of the automobile above. Theuse of a special split nut through which our jack screw, passes permits almost instantaneous initial adjustment to position before applying the lifting force, and as quick a removal of the screw. a

Other features are the adjustability of the carriage, construction of the frame, extendibility to straddle any hoist frame or garage pit, etc.

In the drawing, I, 1, indicate in dotted lines the frame or horizontal spaced steel beams of the conventional automobile cylinder or hydraulic hoist, and upon which automobiles are elevated: H 15 for servicing, and 2 represents the ends ofour' jack frame supported on the lower flanges of the beams, and with the jack-screw 3 of our jackpositioned in about the middle of the frame as for applying. against a portion of the elevated automobile not shown.

The frame of our jack maybe rigid, but is preferably made extendible to straddle any distance between hoist beams, I, or across any garage pit for use on cars where the work is done. from,the pit. In the drawing the extendible frame is shown composed of an outer.

section having two angleiron sides 4 and a narrow or inner section having two similar angle iron sides 5 slidable longitudinally within the wider section, and within which inner section is slidably supported a carriage 6 which supports thetwo sections I, 1 of the split nut which engage the jack-screw 3.

The side bars or angle irons 4 and .5 are spaced .at their outer end by members l! which are preferably Z.-irons or their equivalent, riveted or welded to the side bars, and the inner ends of the inner frame section are spaced by a bar 8, whereas the other ends of the outer frame are leftfree of any cross tie which might interfere with the positioning of the jack-screw to any place along the frame, but they are held against spreading by means of a pair of clamps. 9 whichare formed of short angle bars overlapping the upper edges of both frame sides and grooves at ID to receive the upper edges of bars 5. These clamp bars are held in place by bolts l l passing through the lower or horizontal webs. of bars 4 and which may be tightened up to firmly lock the frame sections at any point of extension. so thatit cannot accidentally be retracted to fall off its end supports when in use, It will be noted from Figure 3 that the inner frame'section is spaced inward from the outer frame sides by bolts 1 I, and from Figure 2 also by spacing nuts 12 so that it rests on the lower webs 4 of the outer frame inward of the rounded inner corners common to such angle bars.

The split nut carriage 6 is preferably made of a short section of a channel iron resting upon the horizontal webs 5 of inner frame section bars 5 and is held in sliding relation thereto by a lower plate I 3 which is spaced below the channel section 6 as by blocks l4 and bolts l5 so that plate l3 freely overlaps the margins of webs 5' and comes close to the inner edges of webs 4' to function as a guiding element for sliding the carriage back and forth along the frame.

The jack-screw is provided at its upper end with a loose head or pressure contact member [6 which takes the form of an inverted cup resting on a large hardened ball I! revolvably seated in a retaining socket formed in the end of the screw. The head l6 may be freely lifted off when not in use, and a standing pin I8 is provided on the carriage 6 over which the head may be placed, and the jack-screw withdrawn from the split'nut and laid alongside the carriage when the device is, dismantled for shipping or carrying about.

The two sections of the split nut are horizontally pivoted at their remote ends at I 8', l8" to the sides I9 of a small piece of channel iron 20secured to carriage channel plate 6 by bolts Id.

The form of the split nut halves is best shown in Figure 5 wherein they will be seen to be formed with a thread 2| for about the upper half only and with an enlarged bore below tapered outwardly at 22 to clear the threaded jack-screw 3 when the nut sections are opened to the position shown in Figure 4 to the limit of their rear stop shoulders 23.

Also to be observed is that each nut half is formed with a lower semicircular flange 24 which falls snugly within a circular opening 25 bored through the bottom of the carriage, when the nut is closed, to thus relieve the pivot bolts l8, l8 from spreading tendency of the nut halves. The jack-screw 3 is guided centrally with respect to the nut halves by a loose round bore l3 in lower plate l3.

The nut halves each have a small projecting finger or lug 26 at one lower corner, and a corresponding recess 21 at the other, and are rights and lefts in this respect so that the lug of one will engage the recess of the other and compel both to work together in opening and closing.

Also to be noted is a standing flange 28 on each half with a lug 29 for gripping with the finger to open the nut halves, or striking with a tool.

It should be observed that the pivot points are well below the threaded portions of the nut so that the downward force of the jack-screw tends to hold the nut halves firmly closed while the screw is under pressure of work, as any opening of the nut halves will tend first to lift the jack-screw bodily a short distance before the halves can open.

. At the lowerend of the screw is a suitable lever handle 33 preferably provided with operating cranks 3| at one or both ends.

It may be noted that by reason of the particular construction of our split nut as described, it operates perfectly with a common threaded jackscrew without tendency to separate.

In operation of our improved jack the bracket is extended to the required length to straddle the space over the pit or between the hoist beams l,

clamps 9 are tightened with bolts l I so as to hold the extended bracket frame absolutely rigid, the frame and carriage are moved at right angles to each other to bring the jack-screw directly under the part to be lifted, the screw is simply shoved upward to contact the part to be raised, then let down slightly to close the nut about the jackscrew, and the crank lever 30 turned to apply the power. To release the jack, the screw must first be unscrewed a short distance, the nut opened manually and the screw pulled down, or entirely through the nut if head I6 is removed.

There are some automobile service hoists which employ a couple of hoist cylinders without a connecting frame, or drive-on frame as illustrated by the beams I of Figure l, but each hoist cylinder has its own bracket or fork arms to engage under the axle of the car. For such hoists our bracket may be of modified form as indicated in Figure 6 wherein the horizontal portion of the bracket is shown at 32 with a split-nut carriage l3 slidably supported on it as described for Figure l, and with one end of the bracket formed with a hookportion' 33 formed to engage the upper end of the hoist cylinder or column 34 or the axle bracket 35, and the outer end of the bracket 32 is angularly braced'as by a pair of braces 36 which, at their lower ends engage opposite sides of the cylinder 34 and are tied by a cross bar 37 which rests against the cylinder.

In this modified form the jack-screw 3 is preferably provided with'a vise handle 38 to better clear the braces 36 when operating close to them.

Having thus described our invention and the manner of its use, what we claim is:

1. In a jack of the character described, a bracket comprising a first pair of spaced angle bars provided with means at one end tying the bars together and forming an outwardly directed flange, a second pair of spaced angle bars slidably sup-ported within the first pair in projecting relation to the untied ends of the first pair, means at the outer ends of the second pair of angle bars tying them together and forming an outwardly directed flange, means for locking both pairs of angle bars at various degreesof extension, a carriage slidably supported on the second pair of angle irons, and a jack screw extending through said carriage operating in a split nut supported thereby.

2. In a jack of. the character described, a vertically arranged threaded jack screw, a split nut engaging the screw, said split nut comprising two nut-halves parted along a vertical line, a base plate upon which the nut-halves are supported when closed, and horizontally extending pivots pivoting the nut-halves to said plate for opening and closing. I

3. In a jack of the character described, a vertically arranged threaded jack screw, a split nut engaging the screw, said split nut comprising two nut-halves parted along a vertical line, a base plate upon which the nut-halves are supported when closed, and horizontally extending pivots pivoting the nut-halves to said plate for opening and closing, each nut-half provided with an aligning shoulder centered in an opening in said plate when the halves are closed and preventing the nut-halves from spreading.

4. In a jack of the character described, a vertically arranged threaded jack screw, a split nut engaging the screw, said split nut comprising two nut-halves parted along a vertical line, a base plate upon which the nut-halves are supported when closed, and horizontally extending pivots pivoting the nut-halves to said plate for opening and closing, and means positively connecting the nut-halves together for simultaneous opening and closing.

5. In a jack of the character described, a vertically arranged threaded jack screw, a split nut engaging the screw,'said split nut comprising two nut-halves parted along a vertical line, a base plate upon which the nut-halves are supported when closed, and horizontally extending pivots pivoting the nut-halves to said plate for opening and closing, the pivots of the nut-halves being positioned respectively at opposite sides of said screw and spaced outwardly therefrom and also spaced below the threading of the nut-halves so as to require an upward swinging of the nuthalves in opening them from the screw whereby they are automatically held closed when the screw is under pressure.

6. In the construction as specified in claim 5, a lug formed on each nut-half arranged for striking to open said halves.

RUSSEL ROBISON. GEORGE H. MOSEL. 

